<!DOCTYPE html>
<html>
<head><style type="text/css">
  #first {
    margin-left:4em;
  }
  #last {
    margin-right:4em;
  }
  #central {
    margin-left:5em;
    margin-right:5em;
  }
</style></head>
<body>
    |<span id=first>a</span><span id=central>b</span><span id="last">c</span>|<br>
    |<span id=first>a</span><span id=central>b</span><span id="last">c</span>|
</body>
</html>
